Objectives: Recent clinical trials have implied the cytotoxic and antiproliferative effects of combining 5-fluorouracil and interferon-alpha in the treatment of metastatic renal cell cancer. We therefore conducted an open multicenter trial to test the efficacy of such a combination on this cancer.
Methods: Human lymphoblastoid interferon (3 MIU per patient) was administered subcutaneously three times weekly for 12 weeks, while 5-fluorouracil was administered (600 mg/m2/day) as a continuous infusion for the first 5 days, followed by an intravenous bolus infusion of 600 mg/m2 once a week from the 3rd week until the 12th week.
Results: Of the 63 patients entered into the trial, 55 were eligible and evaluable for systemic toxicities, and 53 were evaluable for their response. All patients had undergone a prior nephrectomy, and their European Cooperative Oncology Group (ECOG) performance status ranged from 0 to 3 (median 0). Three complete and eight partial responses were induced, with an overall response rate of 20.0%. The median time to progression and the median survival time were 11 and 33 months, respectively. World Health Organization grade 3 toxicities were observed in 8 patients; however, no grade 4 toxicities or toxicity-related deaths were noted.
Conclusions: Combination therapy of interferon-alpha plus 5-fluorouracil at the above-described dosage and schedule produced no better responses than interferon monotherapies. Prolongation of survival could be attributable to the fair performance status of the patients. This regimen has limited value for the treatment of patients with advanced renal cell cancer.